Diet High in Soybean Oil Increases Susceptibility to Colitis in Mice

Soybean oil (SO), the most prevalent cooking oil in the United States, consists primarily of linoleic acid (LA, C18:2 omega-6), a polyunsaturated fatty acid positively linked to the development of ulcerative colitis (UC) in humans. Here, we show that dietary SO increases intestinal epithelial barrier permeability and susceptibility to colitis in mice. It also disrupts the balance of isoforms encoded by the UC susceptibility gene Hepatocyte Nuclear Factor 4 (HNF4), which in turn impacts barrier function and IBD susceptibility. The SO diet causes gut dysbiosis, including an increased abundance of an adherent, invasive Escherichia coli (AIEC) which can use LA as a carbon source. Metabolomic analysis indicates that gut bacteria and the SO diet can alter levels of LA and its oxylipin and endocannabinoid metabolites in the gut. Our results suggest that an SO-enriched diet increases susceptibility to colitis due to effects on intestinal HNF4, microbiota and LA metabolites.